With the use of a custom field with colour coding to sort tasks, the colours show up on the various tasks in the timeline view. However there is no easy way to identify what each colour signifies for a given task, or even on which category are the tasks being colour coded in since the custom field selected does not show on the view, but has to be accessed with 2 steps on the top right menu. It would be much easier if there was simply a dialog box (floating or fixed) that showed on what custom field’s bases the tasks are being coloured, and what those colours mean.